It's the music of silence. With this radical experiment in the field of inaudible music, you can explore the very subtle and almost immaterial transient between the sound and the silence, the music and the background noise of your room.
Once I wake up in the middle of the night and notice some very quiet, but distinct low humming noise. I explored the room and realized it were loudspeakers. Oh, - I thought. Just some interferences in the electric circuit. I turned the amplifier off. The noise was still there. I plug
it off the electric outlet - nothing. I cut off the wires from the amplifier to the speakers, so it was physically impossible for any sound to appear - and it was still there, almost indistinguishable, but very definite. I still never managed to explain that...
Headphones are highly recommended, as you are entering the quite zone. Not mandatory, though, as with loudspeakers you may experience even more drastic effect.